Telkom useless

Hi. I would like to know why Telkom gets away with debiting my account for a mistake that they made and then going back and forth with Isaac from Telkom Canal walk which promised me he will sort it out. Emails back and forth with him for over 3 months and still nothing is sorted. I receive a email from him this morning telling me that they won't be crediting my account for what is rightfully due to me. How does this make sense how are they allowed to do this. I am sick and tired of these companies just doing whatever they want.